Mandibular staple and drill guide

ABSTRACT

A drill guide for mandibular staples is adapted to accurately align a drill for drilling fastener holes in the mandibular lower jaw portion at precisely located positions for the attachment of fasteners therethrough by means of a staple to retain a dental appliance in secure position on the mandibular jaw portion. A Vshaped arcuate groove in the top of the drill guide registers with the center line of the drill guide holes for cooperative registry and alignment with the undersurface of the mandible. A staple has a lower cross plate which is arcuate to conform to the curvilinear shape of the front section of the jaw bone. Attached to said plate are a plurality of fasteners adapted to protrude into and selectively through the jaw bone in accordance with the holes previously drilled. The fasteners are electron-beam-welded to the lower cross plate for a metal-to-metal relation preventing corrosion between the parts and to provide increased strength. The staple is made of a titanium alloy with about 6 percent aluminum and about 4 percent vanadium, to be corrosionresistant.

United States Patent [191 Small MANDIBULAR STAPLE AND DRILL GUIDE Irwin A. Small, 751 Chestnut, Birmingham, Mich. 48088 [22] Filed: Aug. 28, 1974 21 Appl. No.: 501,318

[76] Inventor:

Primary Examiner-Robert Peshock Attorney, Agent, or Firm-Cullen, Settle, Sloman & Cantor [57] ABSTRACT A drill guide for mandibular staples is adapted to ac- [451 Jul 22, 1975 curately align a drill for drilling fastener holes in the mandibular lower jaw portion at precisely located positions for the attachment of fasteners therethrough by means of a staple to retain a dental appliance in secure position on the mandibular jaw portion. A V- shaped arcuate groove in the top of the drill guide registers with the center line of the drill guide holes for cooperative registry and alignment with the undersurface of the mandible. A staple has a lower cross plate which is arcuate to conform to the curvilinear shape of the front section of the jaw bone. Attached to said plate are a plurality of fasteners adapted to protrude into and selectively through the jaw bone in accordance with the holes previously drilled. The fasteners are electron-beam-welded to the lower cross plate for a metal-to-metal relation preventing corrosion between the parts and to provide increased strength. The staple is made of a titanium alloy with about 6 percent aluminum and about 4 percent vanadium, to be corrosion-resistant.

PATENTEDJUL 22 ms SHEET FIG] MANDIBULAR STAPLE AND DRILL GUIDE REFERENCE TO RELATED PATENTS The present invention is an improvement over applicants prior US Pat. No. 3,414,975 and US. Pat. No. 3,664,022.

BACKGROUND OF THE INVENTION The present invention relates to drill guide for mandibular staples and to the construction of the mandibular staple.

Heretofore, in the use of dental appliances of removable nature, particularly with reference to the lower mandibular jaw. natural suction of the dental appliance or cohesion is often reduced due to the aging and wasting away ofjaw bone tissue. Various means are known to be employed in an effort to retain and anchor the lower removable dental appliance against accidental dislodgement from the jaw bone. However, the use of adhesives or known mechanical devices heretofore have been ineffective and inefficient for the intended purpose.

BRIEF DESCRIPTION OF THE INVENTION It is the object of the present invention to provide a mandibular staple which is accurately secured to the mandibular jaw bone beneath the subcutaneous tissue and which. once secured in place by a pair of threaded fasteners. is so arranged that the threaded fasteners themselves are adapted to be interlockingly nested within undercut apertures provided in the dental appli ance to anchor the dental appliance against accidental displacement with respect to the jaw bone.

It is another object to provide an improved drill guide in the form of a jig bore for mandibular staples used in the mechanical attachment of dental appliances to the jaw bone of a patient. The present improved drill guide provides an accurate means for guiding the drilling of apertures through a mandibular jaw bone, be it human or animal, and which apertures at accurately spaced points are adapted to receive a mandibular staple made of metal provided with fastening means thereon to securely engage the jaw bone and to provide an interlock with the dental appliance normally removably mounted on the jaw bone.

The accompanying drawings illustrate a preferred embodiment of the invention in which:

FIG. 1 is a side elevational view of the present improved mandibular drill guide shown in attached drilling position on the curvilinear front end of the mandibular jaw bone;

FIG. 2 is an elevational view taken in the direction of arrows 2-2 of FIG. 1;

FIG. 3 is an enlarged perspective rear view thereof;

FIG. 4 is a side view of the mandibular staple;

FIG. 5 is a plan view thereof;

FIG. 6 is a composite illustration showing the present improved staple in attached position with the dental appliance indicated on the jaw bone in dash lines;

FIG. 7 is a bottom plan view of the staple;

FIG. 8 is a fragmentary vertical section of the drill guide of FIG. 1, on an increased scale.

DETAILED DESCRIPTION OF THE INVENTION FIGS. 1 and 6 illustrate a mandibular jaw bone 10, which could be either human or animal, and which is adapted to receive a removable lower dental appliance 12, FIG. 6. Mounted upon jaw bone 10 is the present improved mandibular staple, shown in detail in FIGS. 4, 5 and 7.

In FIGS. 4 and 5 the improved mandibular staple 14 includes a lower flat support plate 16. In the attachment of the improved mandibular staple to the jaw bone, support plate 16 is adapted to abut against the underside of the jaw bone, FIG. 6. The support plate 16 is arcuate in plan so as to correspond to the curvilinear shape of the front end 11 of the jaw bone.

From the upper surface of the support plate 16 extend a first set of staple securing pins 18 which are welded to the support plate. The first set pins are slightly upwardly tapered and provided at the upper end with a mushroom head 20. These pins 18 are equally spaced along the surface of plate 16. Extending from the support plate is another set of threaded locator pins 22 likewise secured to plate 16. Each of the 10- cator pins are disposed intermediate a pair of adjoining securing pins.

A pair of outer rods 24 and 26 are likewise secured to plate 16. These are for full extension through jaw bone 10. The outer rods are adapted to extend through predrilled holes provided in the front end portion 11 of the jaw bone. The pins 18, 22, 24 and 26 are electron beam-welded to support plate 16 as shown in FIG. 7. There is, thus, a metal-to-metal relationship between said pins and plate, as in a unit cast device. There is no interface between the metal parts and, thus, no chance for later corrosion. Such welding gives great strength of the pin attachment to the curved plate. There is no physical space between pins and plate. The electron beam welding prevents any variation in oxygen concentration. If oxygen was allowed to change its concentration when buried in the body, it would cause corrosion.

The mandibular staple and nuts 27, 28 are made of a titanium alloy containing about 4% vanadium and about 6% aluminum. The staple is, thus. corrosionresistant.

Lock nuts 27 are threaded over rods 24, 26 into abutment with the jaw bone 10. Nuts 28 are then threaded over said rods down to the desired elevation. The lock nuts are then adjusted to apply locking pressure to the nuts 28. The lock nuts take the place of acrylic glue used heretofore for anchoring nuts 28. Nuts 28 may be raised and lowered by releasing the pressure of the lock nut, to accomodate variations in jaw size.

In assembly, FIG. 6, after the nuts 28 have been threaded over the outer rods, the free ends of the rods extending above the nuts are cut off. The dental appliance, indicated in broken lines at 12 in FIG. 6 is provided with spaced apertures which, interlockingly engage nuts 28.

In the application of the mandibular staple 14 to the jaw bone 10 by a dental surgeon. the tissue of the jaw bone is carefully loosened and moved away from the mandibular bone and the plurality of holes and blind apertures provided in the jaw bone 10 by means of the present improved drill guide. Thereafter the staple 14 with locator pins 18-22 and long securing rods 24-26 are aligned with the apertures provided in the jaw bone for attachment to the jaw bone. The tissue of the jaw bone eventually grows together again around the apertures.

With reference to FIGS. 1 through 3, the drilling of the respective apertures through the curvilinear front section of the jaw bone 10, presents the most significant problem in the accurate application of the improved mandibular staple 14 so as not to have the staple bind or otherwise damage the jaw bone or to cause subsequent later problems and injury. Thus. the respective apertures must be drilled such as to be in perfect alignment with and corresponding to the spacing of locking pins 18, locator pins 22 and outer fastening rods 24-26 of the staple. It is essential that the drilled apertures through the jaw bone be accurately located with respect to the jaw bone centerline and inwardly of the open nerve centers 13 of the jaw bone.

The present improved drill guide 32 consists of an elongated post 34 which at the upper end supports an upper arm 36 and also supports a lower arm 38 which is slidable along the post towards or away from the upper arm. The inner surface of post 34 has rack teeth 40 engaged by a gear 42 journaled within an enlarged rear portion 39 of lower arm 38.

The gear is rotatable on a shaft 41 which carries a handwheel 44 at its outer end for rotation of the gear 42. Thus. the lower arm can be moved longitudinally along the post 34. The enlarged portion 39 of the lower arm carries a lock screw 46 to lock the lower arm in the desired adjusted position relative to the upper arm.

The front end of the lower arm 38 expands into a transverse curvilinear shaped drill guide portion 48 which. as shown in FIG. 3, is provided with a first set of apertures 50 and a second set of apertures 52. the apertures 50 and 52 in the drill guide portion 48 are adapted to guidingly receive drill 72 for drilling holes in the jaw bone for attachment of the staple l4, and thus correspond in spacing and number to the spacing and number of locking pins 18-22 and fastener rods 24-26 of the staple 14. Thus. the apertures 50 are adapted for drilling apertures for the threaded locator pins 22 and fastener rods 24-26 whereas the apertures 52 are adapted for drilling apertures for the locking pins 18.

The arcuate shape of the drill guide corresponds to the curvilinear shape of the support plate 16 of the staple 14. As seen in FIG. 1, the rear of the drill guide portion 48 is slotted from end to end as at 54, intersecting the apertures 50 and 52 to provide a lateral opening for each of the apertures which permits powdered bone material and bone chips to be expelled during the drilling operation so as not to accumulate and clog the apertures.

The upper surface of the drill guide portion 48 is provided with a double row of upwardly protruding teeth 56 extending along the opposed outer edges of the drill guide portion. On assembly of the drill guide 32 to the jaw bone 10, these teeth are adapted to bite into the lower surface of the jaw bone upon adjustment of the lower arm 38 to lock the drill guide portion 48 in place. in order to prevent slipping during the drilling operation.

A curved groove 57 of V shape, FIG. 8, is formed in the upper surface of the drill guide portion 48 between and below teeth 56 corresponding to the center of the drill holes 50, 52 of the drill guide. The groove helps to center and locate the exact center of the curved inferior border of the mandible. This is important for improved locking ability when the drill guide and director rod are tightenedtogether for drilling, FIG. 1. It is important to locate the exact center of the inferior border so that the drilled holes can be placed very accurately.

As described in my US. Pat. No. 3,664,022, the front end of the upper arm 36 supports a yoke member 58 which extends transversely of the arm to both sides thereof. Both outer ends of the yoke member are formed cylindrically as at 60 and 62, and each supports a locator pin 64, 66 for extension downwardly towards the drill guide portion 48. The locator pins 64-66 are yieldably supported for relative up or down movement at opposite ends of a centrally pivoted see-saw lever 68 which extends longitudinally through the yoke member 58 and is pivotally secured therein at 70. When one locator pin is moved upwardly, the other opposite locator pin is moved downwardly. This pivotal reciprocating arrangement of the locator pins 64-66 accomodates uneveness in the jaw bone. The lower ends of each of the locator pins 64-66 carry a toothed abutment 65 and 67.

The pivotal locator pins 64-66 are positioned in vertical alignment with a respective outer end aperture 50 of the drill guide portion 48 on the lower arm 38.

Referring to FIGS. 1 and 6, the drill guide is attached to the curved front end 11 of the lower jaw bone 10 of the patient after first pulling back the tissue around the portions of the jaw bone which are to be drilled. The lower arm 38 of the drill guide assembly 32 is adjusted such as to abut against the underside of the curved front portion 11 of the jaw bone to clamp the jaw bone between the drill guide member 48 and the upper locator pins 64-66 which accurately mark the position for the extension of the securing rods 24-26 of the staple through the jaw bone.

The V groove 57 in the upper surface of the drill guide portion guides the lower jaw bone into accurate registry. The surface teeth 56 of the drill guide portions bite into the jaw bone to prevent lateral or rotational displacement of the drill guide during drilling. The curvature of the drill guide member corresponds substantially with the curvature of the front end 1 1 of the mandibular jaw bone 10 to properly drill the apertures for the staple 14 along an arcuate path.

CONVENTIONAL OPERATION After the drill guide has been attached to the lower mandibular jaw bone of the patient, a drill 72, FIG. 1, of the proper size is selected to first drill the two outer apertures in the jaw bone which are adapted to receive the securing rods 24-26 of the staple. After the first through aperture is drilled through the mandibular jaw bone by guidance of the drill through an outer end aperture 50 in the drill guide member, a Kirschner wire of proper diameter is inserted through the drill guide aperture 50 and through the aperture which has been drilled through the jaw bone for further anchoring the drill guide assembly 32 in its previously located positon on the jaw bone to avoid accidental displacement during drilling of the remainder of the apertures.

The second. opposite outer end aperture is then similarly drilled through the jaw bone by utilization of the opposite outer end aperture 50 in the drill guide and a second Kirschner wire of proper diameter is inserted through the drill guide aperture and the drilled aperture in the jaw bone whereby the drill guide assembly is now anchored at two spaced points to positively prevent any displacement.

Thereafter, the remainder of the intermediate blind apertures are drilled on the jaw bone for insertion of the locator pins 22 of the staple, utilizing a drill of the same size as previously employed for the outer end apertures. This drill. however. will be provided with an adjustable stop at a proper distance from its tip, for drilling blind apertures. The apertures for the locator pins 22 do not extend all the way through the mandibular jaw bone. Similarly. another set of blind apertures is drilled into the jaw bone in properly located positions to receive the locking pins 18 of the staple.

Once all the apertures have been drilled through the jaw bone at their preselected accurate locations. the drill guide assembly is removed from the jaw bone and the staple is properly attached by means of the drilled apertures in the jaw bone. The staple I4 is assembled to the jaw bone from underneath. such that the opposed outer end securing rods 24-26 extend through the outer-most drilled bores in the jaw bone and the intermediate locator and locking pins 18-22 extend into their respective blind apertures. The staple I4 is hammered in place.

After the staple 14 has been properly attached to the jaw bone. the lock nuts 27 are threaded over rods 24, 26 to the jaw bone. The securing nuts 28 are threaded down onto said rods to the desired location adjacent the jaw bone. The lock nuts are then adjusted into pressure engagement with nuts 28. Thereafter, the free ends of the securing rods 24-26 immediately above the nuts 28 are cut away. The dental appliance 12, FIG. 6, is then placed on the jaw bone in such fashion that the nuts 28 and the lock nuts 27 are in alignment with undercut apertures previously provided in the dental appliance to anchor the dental appliance against accidental displacement with respect to the jaw bone 10.

After the staple 14 has been in place for a certain time within the jaw bone, the previously penetrated subcutaneous and bone tissue around the locations of the apertures in the jaw bone will grow back into place and around the mutiple locking and securing pins of the staple.

I claim:

I. In a drill guide assembly for mandibular staples adapted for drilling a plurality of apertures in accurately located positions through a jaw bone; said drill guide assembly having an elongated post having a first arm member extending therefrom, a second arm member longitudinally movable along said post towards and away from said first arm member, means to lock said second arm member in adjusted position relative to said first arm member. said first arm member carrying a pair of spaced locator pins. said second arm member carrying a jig fixture at its outer end, said jig fixture being arcuate in a horizontal plane and having a plurality of spaced apertures extending therethrough. said apertures being located along an arcuate line. the outermost of said apertures being in vertical alignment with said pair of spaced locator pins of said first arm;

the improvement comprising spaced arcuate rows of teeth protecting outwardly from the top surface of the jig fixture in respective alignment with the arcuate inner and outer surfaces thereof;

and an arcuate grooved portion of V shape in the top surface of said jig fixture below and between said teeth; said locator pins of said first arm member being adapted to be placed in position on the upper surface of said jaw bone at a pair of prelocated points;

said jig fixture of saidsecond arm member being adapted to cooperatively receive and center along its V groove the depending undersurface of the jaw bone and to clampingly engage the lower surface of said jaw bone upon relative adjusting movement of said second arm member towards said first arm member along said post to cause said teeth on the upper surface of said jig fixture to bitingly engage said jaw bone to prevent displacement of said drill guide when said second arm member is locked in position;

the arcuate arrangement of said plurality of apertures corresponding substantially to the curvilinear shape of said jaw bone;

and each of said apertures being adapted to guidingly receive a drill for drilling a plurality of apertures in said jaw bone at accurate predetermined locations.

2. In a mandibular staple adapted for attachment to a jaw bone to locate and retain a dental appliance on said jaw bone. said mandibular staple having an elongated support plate; a pair of threaded securing rods extending upwardly from said support plate in parallel direction from both ends thereof; a plurality of locking pins disposed between said pair of securing rods extending upwardly from said support plate in parallel direction with said securing rods, and a plurality of locating pins extending from said support plate located between said locking pins and in parallel alignment therewith; said locking pins and said locating pins being of substantially shorter length than said pair of outer end securing rods;

the improvement comprising a lock nut threaded over each securing rod adapted for positioning adjacent the jaw bone;

and a nut threaded over each securing rod adapted for positioning adjacent said jaw bone;

said lock nuts adapted for applying securing retaining pressure on said nuts respectively, said latter nuts adapted for retaining engagement within mating apertures prelocated in said dental appliance.

3. In the mandibular staple of claim 2, said securing rods, locking pins and locating pins being electronbeam-welded to said support plate in metal-to-metal relation without interface.

4. In the mandibular staple of claim 2, said plate, rods. pins, fastener nuts and lock nuts being of titanium alloy of about 6% aluminum and about 4% vanadium, approximately.

5. In the mandibular staple of claim 3, said plate, rods. pins, fastener nuts and lock nuts being of a titanium alloy of about 6% aluminum and about 4% vana- 

1. In a drill guide assembly for mandibular staples adapted for drilling a plurality of apertures in accurately located positions through a jaw bone; said drill guide assembly having an elongated post having a first arm member extending therefrom, a second arm member longitudinally movable along said post towards and away from said first arm member, means to lock said second arm member in adjusted position relative to said first arm member, said first arm member carrying a pair of spaced locator pins, said second arm member carrying a jig fixture at its outer end, said jig fixture being arcuate in a horizontal plane and having a plurality of spaced apertures extending therethrough, said apertures being located along an arcuate line, the outermost of said apertures being in vertical alignment with said pair of spaced locator pins of said first arm; the improvement comprising spaced arcuate rows of teeth protecting outwardly from the top surface of the jig fixture in respective alignment with the arcuate inner and outer surfaces thereof; and an arcuate grooved portion of V shape in the top surface of said jig fixture below and between said teeth; said locator pins of said first arm member being adapted to be placed in position on the upper surface of said jaw bone at a pair of prelocated points; said jig fixture of saidsecond arm member being adapted to cooperatively receive and center along its V groove the depending undersurface of the jaw bone and to clampingly engage the lower surface of said jaw bone upon relative adjusting movement of said second arm member towards said first arm member along said post to cause said teeth on the upper surface of said jig fixture to bitingly engage said jaw bone to prevent displacement of said drill guide when said second arm member is locked in position; the arcuate arrangement of said plurality of apertures corresponding substantially to the curvilinear shape of said jaw bone; and each of said apertures being adapted to guidingly receive a drill for drilling a plurality of apertures in said jaw bone at accurate predetermined locations.
 2. In a mandibular staple adapted for attachment to a jaw bone to locate and retain a dental appliance on said jaw bone, said mandibular staple having an elongated support plate; a pair of threaded securing rods extending upwardly from said support plate in parallel direction from both ends thereof; a plurality of locking pins disposed between said pair of securing rods extending upwardly from said support plate in parallel direction with said securing rods, and a plurality of locating pins extending from said support plate located between said locking pins and in parallel alignment therewith; said locking pins and said locating pins being of substantially shorter length than said pair of outer end securing rods; the improvement comprising a lock nut threaded over each securing rod adapted for positioning adjacent the jaw bone; and a nut threaded over each securing rod adapted for positioning adjacent said jaw bone; said lock nuts adapted for applying securing retaining pressure on said nuts respectively, said latteR nuts adapted for retaining engagement within mating apertures prelocated in said dental appliance.
 3. In the mandibular staple of claim 2, said securing rods, locking pins and locating pins being electron-beam-welded to said support plate in metal-to-metal relation without interface.
 4. In the mandibular staple of claim 2, said plate, rods, pins, fastener nuts and lock nuts being of titanium alloy of about 6% aluminum and about 4% vanadium, approximately.
 5. In the mandibular staple of claim 3, said plate, rods, pins, fastener nuts and lock nuts being of a titanium alloy of about 6% aluminum and about 4% vanadium, approximately. 